Posted
by
Roblimo
on Thursday June 02, 2011 @10:12AM
from the it's-life-Jim-but-not-as-we-know-it dept.

An anonymously submitted article says, "For the first time, scientists have found complex,
multi-celled creatures living a mile and more below the planet’s surface, raising new possibilities about the spread of life on Earth and potential subsurface life on other planets and moons (abstract). ... The research is likely to trigger scientific challenges and cause some controversy because it places far more complex life in an environment where researchers have generally held it should not, or even cannot, exist."

* The link doesn't work at all* I come read the comments and see others are having the same problem, so I go to log-in and comment* If I try to log in, my username password appears behing a banner ad.* When I do succeed in logging in, I can no longer see any comments.* So, here I am posting as AC.

What do you mean, "*The worms* cut the cable"? How could they cut the cable, man? They're animals!
Oh dear Lord Jesus, this ain't happening, man... This can't be happening, man! This isn't happening! Aw, man. And I was getting short. Four more weeks and out. Now I'm going to buy it on this rock! It ain't half-fair, man! Four more weeks! Aw, man!

I wonder if life could actually start in an environment like that, as opposed to starting in the oceans like it did on earth and then migrating downwards over millions of years. If life needs relatively hospitable conditions to start then we should not expect to find life on planets with only harsh environments.

I wonder if life could actually start in an environment like that, as opposed to starting in the oceans like it did on earth and then migrating downwards over millions of years. If life needs relatively hospitable conditions to start then we should not expect to find life on planets with only harsh environments.

This answers a different question - essentially "what are the (current) parameters for environmental conditions that allow life (as we know it)". We just kicked that can down the road a bit. Obviously, if lifeforms cannot survive in a particular environment it makes it unlikely that the started out in that environment but the converse isn't necessarily true. The planetary environment was markedly different when life started - warmer temperatures, little oxygen and just the fact that there weren't any oth

Don't see anything fundamentally against it. However, as the emergence of life seems to be a rather rare event, I still favor the oceans - more chemicals there, more energy. Everything going on in the deep biosphere is damn slow due to resource constraints. In my opinion, the chance for life emerging is still higher in the oceans.

More from the article: "The research is likely to trigger scientific challenges and cause some controversy because it places far more complex life in an environment where researchers have generally held it should not, or even cannot, exist."

I thought they stopped saying that after finding life in the Challenger Deep [nationalgeographic.com] section of The Mariana Trench.

It's somewhat different, though - the deep sea regions still get a constant supply of nutrients that basically rain down from the more productive ocean layers. In the deep geosphere, all the worms can live off are lithotrophic bacteria that live from certain anorganic chemicals found down there. But yeah, in the end, not surprising - life seems always to find a way.

lithotrophic bacteria that live from certain anorganic chemicals found down there

According to the team that found these nematodes (and the bacteria five years earlier), the bacteria lives off of radiation in the rocks, not chemistry. (Come back in a few years to see what eats the worms?)

lithotrophic bacteria that live from certain anorganic chemicals found down there

According to the team that found these nematodes (and the bacteria five years earlier), the bacteria lives off of radiation in the rocks, not chemistry. (Come back in a few years to see what eats the worms?)

How many times now have we found life in extreme conditions where we were convinced life couldn't exist?

And given that we believe life adapted to the environment on Earth (early organisms didn't even breathe oxygen) then why we are so convinced that theoretical life in the universe must conform to the rules on Earth?

I wouldn't say that we generally assume conditions to be necessarily earth-like for life to arise. However, there are hard constraints on conditions that allow complex chemistry to happen - and those limit the habitable range. Basically, the only reasonably complex chemistry happens with carbon - so you are automatically limited to conditions where carbon compounds are stable. That sets an upper bound for temperatures, for example. On the other hand, you want some reactivity - life has to be dynamic, after all. That gives you a lower bound for temperatures. Earth happens to be in the middle there, but there are quite some deviations from earth-like conditions where life would be possible, biochemically.

We're now seeing examples where DNA can be built using arsenic. The principle still applies that life on Earth is believed to be a response to the environment on Earth. Why wouldn't that be true elsewhere?

Our entire precept of what is required for life to exist could be flawed based upon our limited perspective.

The potentially arsenic-"based" bacteria are still carbon based. Only the phosphate links in the sugar-phosphate backbone of their DNA are possible replaced by arsenate links, possible the phosphates in their ATP or GTP, too. This is interesting, but not too surprising, as arsenic is chemically quite close to phosphorus.

I am not arguing that earth-like conditions are a necessity, but that there are hard limits on conditions. If you want to have life you need a chemistry that is sufficiently complex to store information and to build structures. With that, you are down to carbon. Nothing else (with the very, very low possibility of silicon being an exception) makes a sufficiently complex chemistry. You need metabolism, so you need some kind of energy gradient and therefor chemical dynamics on a timescale that makes exploiting that gradient possible. Another hard limit. Those limits are not given by taking earth as a standard, this is basic thermodynamics, in the end.

Ah, ruby, polite as ever. Now please show me the functional diversity on phosphazenes, anything except being a base? And show me the stable phosphazenes without carbon based attachements. Also, show me a phophazene polymer that could be used for information storage. They are useful reagents, but making up a biochemistry on that basis? Highly doubtful.

see, there you go with your carbon chauvinism again, only knowing the organic nonlinear phosphazenes, while nonlinear inorganic ones such as with sulfur exist. Information storage can be a simple matter of substituting those "R"s the polymer chemists so love to put in their diagrams with some variety of other things. Worth mentioning too that many metal oxides can form nonlinear polymers including cyclical patterns. A life form based on such things might exist in conditions we would think of as totally

My question is this: just because you find life in extreme conditions, does not mean it can develop in those conditions. It seems more likely to me that life develops in more ideal conditions, then migrates to areas where conditions are more harsh. Am I being too skeptical or pessimistic?

I tend to agree with that thought. Looking at human history as an example, we have adapted to live in some very extreme conditions, albeit we often create artificial devices to do so, however, it still stands that we have found a way to live in both arctic climates as well as deserts and tropical forests for centuries. While animals don't have the mechanical capacity we do, life still adapts to new challenges and environmental changes.

But (unless I missed a memo) we actually don't know what conditions the first life formed in. Although we tend to focus on the ocean environment, it's entirely possible that the first cells formed in some more exotic deep crevise and only later migrated to the surface. In many ways, walking around in the open air makes *us* one of the most exotic extremophiles of the world.

But (unless I missed a memo) we actually don't know what conditions the first life formed in. Although we tend to focus on the ocean environment, it's entirely possible that the first cells formed in some more exotic deep crevise and only later migrated to the surface. In many ways, walking around in the open air makes *us* one of the most exotic extremophiles of the world.

Here is one of the later memos [nih.gov]. Yes, the conditions on earth at the beginning of biogenesis (as opposed to the other Genesis) were very, very different that the current environment. We wouldn't like it at all. Many theories of biogenesis use solid phase chemicals (like various clays) as early catalysts and / or structural parts of the earliest life forms.

Many biological reactions at surface pressures and temperatures require catalysts called enzymes to proceed. Protein synthesis and the citric cycle are two basic examples. These do not require catalysts at high temperature and pressures according to work Robert Hazen of Carnegie Institute.

After life began it evolved enzymes to expand into other ecological niches. For example, the ocean surface is an energy rich area with solar radiation.

I agree with you, but this still has implications for the possibility of extraterrestrial life. Mars used to be much warmer and wetter, so it is possible that life developed under more ideal conditions and continued to survive under harsh conditions.

But my doubts come because TFA says the worms were "found in water flowing from a borehole about one mile below the surface". That seems like plenty of opportunity for contamination. I'd be very skeptical that there are worms one mile below the surface of the earth in locations not touched by human activity. If you found them in a freshly drilled borehole with no water flowing that would be much more interesting.

By the borehole, which sounds like it's been there for a while. By the water, which may be flowing into the borehole from the surface. By the humans, which from looking at the picture are gathering samples without wearing gloves or a mask, or at least are visiting the area without gloves and masks. I don't see any precautions against these.

A primary hurdle the team had to overcome was proving that the nematodes had not come into the mines on the shoes or clothing of miners or through mine ventilation water. The contamination issue was resolved through extensive testing of the soil and mining water, which contains two disinfectant bleaches that would kill nematodes.

Neither. You've just proposed a hypothesis. That's what all of science is about.

Really, it's ok to say "we don't know". We can't say for sure if it developed down there or migrated. I doubt the scientists said anything to that effect, either. Or even if they did, most of them wouldn't. Science articles are typically rife with horribly inaccurate "paraphrasing" because the journalist doesn't know what they're talking about and try to translate scientific jargon to "layman" speak.

In principle, that seems plausible. Life could have migrated there, not evolved. That may be the case for the worms, but the bacteria they feed on seem different. Feeding off radiation in a high-pressure, anaerobic environment? That seems too big a difference to easily explain via evolution from aboveground organisms. I wouldn't rule that out as a possibility, but it still seems dubious.

Earth may have served as an optimal place for life to develop in some areas, and then evolve to tolerate/inhabit less-optimal environs.

That doesn't preclude the idea that the process took place one step earlier, either: that life getting to earth in the first place may have ALSO been a matter of it surviving inhospitable conditions until it reached a place where it could flourish.

The research is likely to trigger scientific challenges and cause some controversy because it places far more complex life in an environment where researchers have generally held it should not, or even cannot, exist.

If the critters have conclusively been found to live there, then people will just have to accept it, recalibrate their views on what's possible, and continue from there. Why the controversy?

Worms make the dirt
And the dirt makes the earth
And all of the roots have a place to sleep now
All the chanuks have squash to eat now
Worms make the dirt
And the dirt makes the earth
And people hold hands and feel terrific
Food comes from dirt
It's scientific

If the Rossi/Focardi eCat (a claimed nickel-hydrogen LENR cold fusion device) really works, maybe cold fusion also happens at the boundary of the Earth's nickel-iron crust? And maybe the core even ejects neustrons, as suggested about the sun? And the end result might be abiotic oil and other "food" that could support an underground biosphere? Could life have even started down there (if bacteria did not come from beyond the solar system)? What other scientific dogma remains to be overturned? Related comment

I just thought I would mention Thomas Gold [wikipedia.org]'s book The Deep Hot Biosphere [barnesandnoble.com]. Gold's thesis is that "fossil fuels" aren't, and have an abiological origin, much like the hydrocarbons we can see in interstellar nebulae. An essential part of the theory is that "extremophiles" aren't all that rare, and permeate the earth down to unsuspected depths... that explains why the oil coming up out of the ground looks biological in origin (handedness): it's been messed with by the deep bacteria.

They were found at depths ranging from 900m down to 3.6km (3000ft-2mi). Carbon dating their environment showed they'd been there for at least 3000 years. (The team that found this also found radiation eating bacteria at similar depths five years ago, they been through the standard objections before.)

I don't think it's especially radioactive. It's just rock. So it's the same level of radiation that radiometric dating has been calibrated for. (That said, IDFK. And the article I read had the phrase "they carbon-dated the water", so I don't know if they are using the phrase "carbon-dating" as a dumbed down way of saying "radiometric dating", or "water" to mean "nematode's environment". Either way, not much help there.)

Very interesting. So far, I was only aware of the archaia that seem to be responsible for oil production and other mineral deposits.

Nice troll. Abiogenic production of oil has been completed refuted [wikipedia.org] as a valid hypothesis.

Although the abiogenic hypothesis was accepted by many geologists in the former Soviet Union, it allegedly fell out of favor because it never made any useful prediction for the discovery of oil deposits.

Unless I'm misreading him, GP didn't say anything about abiogenic oil production. He said that oil is produced by archaea [wikipedia.org], which I thought was more or less the standard theory of oil production (plus or minus bacteria).

Hmm. I still think that's not a currently accepted theory. You certainly see archea in wells and in oil tanks, but you see them everywhere. The quick Google search didn't enlighten me much. My reply was assuming that the OP did mean essentially abiogenic oil production, could be wrong.

i've always wondered what creepy creatures will evolve and emerge from landfills millions of years from now.

Why wait millions of years? You can visit retired landfills now and prove your "Landfills eventually yield creepy creatures" hypothesis correct. Some of the most prevalent of the creepy of creatures you'll find there are: Lawyers, Politicians, and Stock Marketeers.

Some say that these life-forms do not emerge from the the abandoned rubbish of society, that they instead are attracted to the Golf Courses built atop the land-fills; To them I must issue a reminder: Correlation is not Causation...